Abbey Slurry Tank - Front ball valve assembly not allowing suction? (See Photos)

Oh ok. That makes sense. I thought that the ball was going up and down the metal tube depending on whether the pump was sucking or blowing. From what i understand you are saying, the ball would stay at the bottom of the assembly at all times except in an emergency when slurry accidentally got sucked into the assembly and only then would the ball rise as the slurry rose inside the metal tube to where it would stop at the top of the assembly unit and cut off the slurry from going any further, in other words into the pump itself.

When i opened the bottom cover of the ball valve assembly unit, the ball seemed quite tight in there. It took me a while to lever the ball down and out of the assembly. Is it supposed to be that tight?

I dont think its rust. There is a bit of crud but not enough to make the ball tight.

Is it possible the ball has swelled? The ball is squishy to feel, as though it is full of air, and after pressing it in about 5mm all around i can feel the hard inner core, but the rubber outing pushes back out again. Just like you would squish a balloon and after you let it go the balloon pushes back out again. So the ball seems to be a sealed unit that is undamaged since it left the factory.

I had to push a long screwdriver up to lever the ball down the tube and even this took me several attempts. The outside of the rubber ball is making contact, all the way around, with the inner surface of the metal tubing of the assembly.

That's interesting. I must take it to my dealer. I have no experience with what these balls should feel like.

Though its puzzling me as to why the tank is able to blow air out the back fine, but wont suck air in at all.

UPDATE

So i managed to fix the slurry spreader. It turns out the problem was indeed the ball inside the ball valve assembly unit directly over the pump. It had swelled to 110mm in diameter and had become squishy. One dealer did not know if a squishy ball was normal, the other one told me it was not and had seen balls become like that before. He gave me a new one, which is solid to feel and 100mm in diameter. Cost €25. So i put the new ball in, gave the inside of the ball valve assembly unit a clean while i had it open (a dirty job as the cover is at the bottom which means all the crud will run down your arm when you stick your arm up there with a rag and some diesel to clean it). Took the spreader for a test run and was sucking and blowing fine.

Many thanks to all the posters you posted here. Hopefully others will find this info helpful at a later date if they find their slurry tank will blow but not suck.

On a side note. When storing the slurry spreader for the winter, should i keep the central back hatch opened or closed? This is the hydraulic hatch which is raised and lowered by the hydraulic oil hose. Does it matter? Or does one setting (raised or lowered) put more pressure on the hydraulic hose for the winter?

So the back hatch would be half open?

I wasn't sure which position (opened or closed) was putting the most pressure on the hydraulic line. So half opened (or half closed depending on which way you look at it) would be best?